WO2011052651A1

WO2011052651A1 - Pulse wave analyzer and recording medium

Info

Publication number: WO2011052651A1
Application number: PCT/JP2010/069093
Authority: WO
Inventors: 森　尚樹; 小椋　敏彦; 和延糸永; 昇三高松
Original assignee: オムロンヘルスケア株式会社
Priority date: 2009-10-30
Filing date: 2010-10-27
Publication date: 2011-05-05
Also published as: RU2012103188A; JP2011092556A; US20120095353A1; RU2570282C2; CN102469942B; JP5287668B2; CN102469942A; DE112010004170T5; US9044145B2

Abstract

Provided is a pulse wave analyzer (100) which calculates pulse wave analysis indices by storing pulse wave waveforms of multiple beat components and analyzing the pulse wave waveforms of the multiple beat components. The pulse wave analysis indices are calculated by collecting the pulse wave shape of each single beat forming the pulse wave waveforms of the multiple beat components and excluding beats which have a low degree of approximation between the collected pulse wave shapes and the pulse wave shape of each single beat from the subjects of calculation of the pulse wave analysis indices.

Description

Pulse wave analyzer and recording medium

The present invention relates to a pulse wave analysis device, and more particularly, a pulse wave analysis device capable of calculating a predetermined pulse wave analysis index by analyzing a pulse wave waveform for a plurality of beats, and a recording recording a pulse wave analysis program It relates to the medium.

Pulse wave analysis is used to measure pulse wave analysis indices such as pulse wave velocity. The pulse wave velocity is used in clinical practice as an index for noninvasively evaluating arterial stiffness.

There are the following techniques for measuring a pulse wave analysis index with high accuracy.
Japanese Patent Laying-Open No. 2006-247221 (Patent Document 1) describes that it is determined from an autocorrelation function waveform whether or not a pulse wave includes noise.

Japanese Patent Application Laid-Open No. 2001-128946 (Patent Document 2) describes that in order to measure accurate pulse wave propagation velocity information, a notch is detected and the pulse wave propagation velocity is calculated from the time difference.

In Japanese Patent Laid-Open No. 10-328150 (Patent Document 3), in order to measure the pulse wave velocity with high accuracy, the pulse wave velocity can be calculated using the maximum slope line and the base line of the heartbeat synchronization wave. Are listed.

In Japanese Patent Laid-Open No. 2008-168073 (Patent Document 4), in order to improve the reliability and efficiency of an arteriosclerosis examination, a feature point of a pulse wave to be acquired is detected, and the pulse wave is clearly indicated. It describes that the waveform is displayed on the screen in real time.

JP 2006-247221 A JP 2001-128946 A Japanese Patent Laid-Open No. 10-328150 JP 2008-168073 A

The pulse wave velocity, which is a kind of pulse wave analysis index, is obtained by the following method, for example. In the case of the brachial-ankle pulse wave velocity (baPWV), which is a form of pulse wave velocity, a PVR (Pulse Volume) is collected by holding the cuff wrapped around the upper arm and ankle at a constant pressure. Recording) Waveforms are recorded for several to a dozen beats. Then, the pulse wave propagation velocity is calculated by detecting the rising position of the pulse wave for each beat for each of the PVR waveforms of the upper arm and the ankle.

In such a method, pulse waves for all the beats are used to calculate a pulse wave analysis index. Therefore, if an arrhythmia or body movement occurs during PVR waveform collection, the pulse wave is disturbed and the measurement accuracy of the index deteriorates. End up. As a result, an erroneous measurement value (inaccurate pulse wave analysis index) may be used for diagnosis.

In addition, the proposals in the above patent documents are not sufficient for calculating the pulse wave analysis index with high accuracy.

The present invention has been made to solve the above-described problems, and its purpose is to record a pulse wave analysis device and a pulse wave analysis program capable of calculating a pulse wave analysis index with high accuracy. Is to provide a recording medium.

A pulse wave analysis device according to an aspect of the present invention includes a storage unit for storing pulse wave waveforms for a plurality of beats, and a process for calculating a pulse wave analysis index by analyzing the pulse wave waveforms for a plurality of beats. And an output unit for outputting the calculated pulse wave analysis index as an analysis result. The analysis processing unit accumulates pulse wave shapes for each beat constituting a pulse wave waveform for a plurality of beats, and calculates a beat with a low degree of approximation between the accumulated pulse wave shape and the pulse wave shape for each beat. To calculate a pulse wave analysis index.

Preferably, the analysis processing unit further calculates the stability of the pulsation by accumulating the degree of approximation of the pulse wave shape used for calculating the pulse wave analysis index, and the output unit calculates the stability. Further output as an index indicating the credibility of the wave analysis index.

Preferably, the storage unit stores a pulse wave waveform for a plurality of beats for each limb, and the analysis processing unit accumulates a pulse wave shape for each beat for each limb, and also has a degree of approximation and a pulse wave. The analysis index and the stability are calculated, and the output unit outputs the pulse wave analysis index having the higher stability as the analysis result.

Preferably, the storage unit stores a pulse wave waveform for a plurality of beats for the left and right limbs, and the analysis processing unit calculates an approximation for each limb, and the higher limb of the limb has a higher degree of approximation. A pulse wave analysis index is calculated using the pulse wave shape.

Preferably, the analysis processing unit calculates the degree of approximation by limiting the range of the pulse wave shape for each beat to the range that affects the calculation of the pulse wave analysis index.

Preferably, the pulse wave analysis index indicates the degree of arteriosclerosis and / or the degree of stenosis of the blood vessel.

More preferably, the pulse wave analysis index includes a pulse wave velocity as an index indicating the degree of arteriosclerosis.

Preferably, a pulse wave detection unit for detecting a pulse wave of the limb is further provided, and the analysis processing unit measures a pulse wave waveform for a plurality of beats based on a detection signal from the pulse wave detection unit.

A recording medium according to another aspect of the present invention records a pulse wave analysis program for causing a computer to function as a device for analyzing a pulse wave. The pulse wave analysis program accumulates a pulse wave shape for each beat constituting a pulse wave waveform for a plurality of beats stored in the storage unit in the computer, and the accumulated pulse wave shape and each beat A step of calculating a pulse wave analysis index by excluding a beat having a low degree of approximation with the pulse wave shape from a calculation target and a step of outputting the calculated pulse wave analysis index as an analysis result are executed.

According to the present invention, it is possible to calculate a pulse wave analysis index using only stable beats that are less affected by body motion. As a result, a highly accurate pulse wave analysis index can be output as an analysis result.

It is a schematic block diagram of the pulse wave analyzer according to the embodiment of the present invention. It is a functional block diagram which shows the function structure of the pulse-wave analysis apparatus according to embodiment of this invention. It is a figure which shows an example of the pulse wave measurement result for every limb part. In embodiment of this invention, it is a figure for demonstrating the calculation method of the approximation degree of the integrated pulse wave shape and each beat. It is a figure for demonstrating the calculation method of a pulse wave propagation distance. It is a flowchart which shows the pulse wave analysis process in embodiment of this invention. It is a figure which shows an example of the exclusion process result in step S108 of FIG. It is a figure which shows the example of an output of the analysis result information in embodiment of this invention. It is a figure which shows the other output example of the analysis result information in embodiment of this invention. It is a figure which shows the further another output example of the analysis result information in embodiment of this invention. It is a figure which shows the pulse wave waveform for several beats of measurement ID1. It is a figure which overlaps and shows the pulse wave shape for every beat of FIG. 11A from the standup position as a starting point. It is a figure which shows the pulse wave waveform for several beats of measurement ID2. It is a figure which overlaps and shows the pulse-wave shape for every beat of FIG. 12A from the standup position as a starting point. It is a figure which shows the pulse wave waveform for several beats of measurement ID3. It is a figure which overlaps and shows the pulse wave shape for every beat of FIG. 13A from the standup position as a starting point. It is a figure which shows the pulse wave waveform for several beats of measurement ID4. FIG. 14B is a diagram showing the pulse wave shape for each beat in FIG. 14A with the rising position as a starting point. It is a figure which shows the pulse wave waveform for several beats of measurement ID5. It is a figure which overlaps and shows the pulse wave shape for every beat of FIG. 15A from the standup position as a starting point. It is a figure which shows the pulse wave waveform for several beats of measurement ID6. FIG. 16B is a diagram illustrating the pulse wave shape for each beat in FIG. 16A with the rising position as a starting point. It is a figure which shows the pulse wave waveform for several beats of measurement ID7. It is a figure which shows the pulse wave shape for every beat of FIG. It is a figure which shows the pulse wave waveform for several beats of measurement ID8. It is a figure which overlaps and shows the pulse-wave shape for every beat of FIG. 18A from the standup position as a starting point. It is a figure which shows the pulse wave waveform for several beats of measurement ID9. It is a figure which overlaps and shows the pulse wave shape for every beat of FIG. 19A from the standup position as the starting point. It is a figure which shows the pulse wave waveform for several beats of measurement ID10. It is a figure which overlaps and shows the pulse wave shape for every beat of FIG. 20A from the standup position as a starting point. It is a figure which shows the pulse wave waveform for several beats of measurement ID11. It is a figure which overlaps and shows the pulse-wave shape for every beat of FIG. 21A from the standup position as a starting point. It is a figure which shows the pulse wave waveform for several beats of measurement ID12. It is a figure which overlaps and shows the pulse wave shape for every beat of FIG. 22A from the standup position as a starting point. It is a figure which shows the pulse wave waveform for several beats of measurement ID13. It is a figure which overlaps and shows the pulse wave shape for every beat of FIG. 23A from the standup position as a starting point. It is a figure which shows the pulse wave waveform for several beats of measurement ID14. It is a figure which overlaps and shows the pulse wave shape for every beat of FIG. 24A from the standup position as a starting point. It is a figure which shows the pulse wave waveform for several beats of measurement ID15. It is a figure which overlaps and shows the pulse wave shape for every beat of FIG. 25A from the standup position as the starting point. It is a figure which shows the pulse wave waveform for several beats of measurement ID16. FIG. 26B is a diagram showing the pulse wave shape for each beat in FIG. 26A with the rising position as a starting point. It is a figure which shows the pulse wave waveform for several beats of measurement ID17. It is a figure which overlaps and shows the pulse wave shape for every beat of FIG. 27A from the standup position as a starting point. FIG. 28 is a diagram showing the relationship between the ranking of the degree of approximation calculated by the apparatus and the ranking of the degree of approximation by the reader when the pulse wave waveform of FIGS. 11A to 27B is targeted. It is a figure which shows the correlation with the order of approximation by an apparatus shown in FIG. 28, and the order of approximation by a reader. It is a figure for demonstrating the calculation method of the pulse wave analysis parameter | index in the modification 2 of embodiment of this invention.

Embodiments of the present invention will be described in detail with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals and description thereof will not be repeated.

<About schematic configuration>
FIG. 1 is a schematic configuration diagram of pulse wave analysis apparatus 100 according to the embodiment of the present invention.

Referring to FIG. 1, pulse wave analysis apparatus 100 includes an information processing unit 1, four detection units 20ar, 20al, 20br, and 20bl, and four cuffs 24ar, 24al, 24br, and 24bl.

The cuffs 24ar, 24al, 24br, and 24bl are respectively attached to the limbs of the person 200 to be measured. Specifically, it is worn on the upper right arm (upper right limb), left upper arm (left upper limb), right ankle (right lower limb), and left ankle (left upper limb), respectively. Note that the “limb” represents a part included in the limb, and may be a wrist, a fingertip, or the like. The cuffs 24ar, 24al, 24br, and 24bl are collectively referred to as “cuff 24” unless they need to be distinguished from each other.

Each of the detection units 20ar, 20al, 20br, and 20bl includes hardware necessary for detecting the pulse wave of the limb of the person 200 to be measured. Since the configurations of the detection units 20ar, 20al, 20br, and 20bl may all be the same, these are collectively referred to as the “detection unit 20” unless they need to be distinguished from each other.

The information processing unit 1 includes a control unit 2, an output unit 4, an operation unit 6, and a storage device 8.
The control unit 2 is a device that controls the entire pulse wave analysis apparatus 100, and typically includes a CPU (Central Processing Unit) 10, a ROM (Read Only Memory) 12, and a RAM (Random Access Memory) 14. Consists of including computers.

The CPU 10 corresponds to an arithmetic processing unit, reads a program stored in advance in the ROM 12, and executes the program while using the RAM 14 as a work memory.

The control unit 2 is connected with an output unit 4, an operation unit 6, and a storage device 8. The output unit 4 outputs the measured pulse wave, the pulse wave analysis result, and the like. The output unit 4 may be a display device constituted by an LED (Light Emitting Diode) or LCD (Liquid Crystal Display), or a printer (driver).

The operation unit 6 receives an instruction from the user. The storage device 8 holds various data and programs. The CPU 10 of the control unit 2 reads and writes data and programs recorded in the storage device 8. The storage device 8 may be constituted by, for example, a hard disk, a nonvolatile memory (for example, a flash memory), or a removable external recording medium.

Here, the configuration of each detection unit 20 will be specifically described.
The detection unit 20br detects the pulse wave in the upper right arm by adjusting and detecting the internal pressure (hereinafter referred to as “cuff pressure”) of the cuff 24br attached to the upper right arm of the person 200 to be measured. The cuff 24br contains a fluid bag (for example, an air bag) (not shown).

The detection unit 20br includes a pressure sensor 28br, a pressure regulating valve 26br, a pressure pump 25br, an A / D (analog to digital) converter 29br, and a pipe 27br. The cuff 24br, the pressure sensor 28br, and the pressure regulating valve 26br are connected by a pipe 22br.

The pressure sensor 28br is a detection part for detecting pressure fluctuation transmitted through the pipe 22br, and includes a plurality of sensor elements arranged at predetermined intervals on a semiconductor chip made of single crystal silicon or the like as an example. The pressure fluctuation signal detected by the pressure sensor 28br is converted into a digital signal by the A / D conversion unit 29br and input to the control unit 2 as a pulse wave signal pbr (t).

The pressure regulating valve 26br is inserted between the pressure pump 25br and the cuff 24br, and maintains the pressure used to pressurize the cuff 24br in a predetermined range during measurement. The pressure pump 25br operates in response to a detection command from the control unit 2, and supplies air to a fluid bag (not shown) in the cuff 24br in order to pressurize the cuff 24br.

The cuff 24br is pressed against the measurement site by this pressurization, and the pressure change corresponding to the pulse wave of the upper right arm is transmitted to the detection unit 20br via the pipe 22br. The detection unit 20br detects the pulse wave of the upper right arm by detecting the transmitted pressure change.

Similarly, the detection unit 20bl includes a pressure sensor 28bl, a pressure regulating valve 26bl, a pressure pump 25bl, an A / D converter 29bl, and a pipe 27bl. The cuff 24bl, the pressure sensor 28bl, and the pressure regulating valve 26bl are connected by a pipe 22bl.

The detection unit 20ar includes a pressure sensor 28ar, a pressure regulating valve 26ar, a pressure pump 25ar, an A / D conversion unit 29ar, and a pipe 27ar. The cuff 24ar, the pressure sensor 28ar, and the pressure regulating valve 26ar are connected by a pipe 22ar.

Similarly, the detection unit 20al includes a pressure sensor 28al, a pressure regulating valve 26al, a pressure pump 25al, an A / D converter 29al, and a pipe 27al. The cuff 24al, the pressure sensor 28al, and the pressure regulating valve 26al are connected by a pipe 22al.

Since the function of each part in the detection units 20bl, 20ar, 20al is the same as that of the detection unit 20br, detailed description will not be repeated. Further, each part in the detection unit 20 will be described by omitting symbols such as “ar” and “br” unless it is particularly necessary to distinguish them.

In the present embodiment, a configuration for detecting a pulse wave using the pressure sensor 28 will be described. However, a configuration for detecting a pulse wave using an arterial volume sensor (not shown) may be used. In this case, the arterial volume sensor may include, for example, a light emitting element that emits light to the artery, and a light receiving element that receives transmitted light or reflected light of the artery irradiated by the light emitting element. Alternatively, it includes a plurality of electrodes, allows a small constant current to flow through the measurement site of the person 200 to be measured, and detects a voltage change caused by a change in impedance (biological impedance) generated according to the propagation of the pulse wave. Good.

<About functional configuration>
FIG. 2 is a functional block diagram showing a functional configuration of pulse wave analysis apparatus 100 according to the embodiment of the present invention.

Referring to FIG. 2, pulse wave analysis apparatus 100 according to the present embodiment functions as adjustment unit 30, pulse wave measurement unit 102, analysis processing unit 104, blood pressure measurement unit 106, blood pressure index calculation unit 108, and output. Part 4 is included. Note that the blood pressure measurement unit 106 and the blood pressure index calculation unit 108 may not be included in the functional configuration of the pulse wave analysis device 100.

The adjusting unit 30 is a functional unit that adjusts the pressure in the cuff 24. The function of the adjusting unit 30 is achieved by, for example, the pressure pump 25 and the pressure regulating valve 26 shown in FIG.

The pulse wave measurement unit 102 is connected to the adjustment unit 30 and the A / D conversion unit 29, and performs processing for measuring a pulse wave (PVR) in each limb. The pulse wave measurement unit 102 adjusts the internal pressure of the cuff 24 by giving a command signal to the adjustment unit 30, and detects cuff pressure signals Par (t), Pal (t), Pbr detected in response to the command signal. (T), Pbl (t) is received. Then, by recording the received cuff pressure signals Par (t), Pal (t), Pbr (t), and Pbl (t) in time series, a pulse wave waveform for a plurality of beats is acquired for each limb. . The pulse wave is measured, for example, for a predetermined time (for example, about 10 seconds).

The pulse wave measurement result by the pulse wave measurement unit 102 may be output to the output unit 4.
FIG. 3 is a diagram illustrating an example of a pulse wave measurement result for each limb. In FIG. 3, the pulse waveform of each limb is shown along the same time axis. As shown in FIG. 3, the rising position of the pulse wave for each beat may be indicated by a broken line or the like.

The analysis processing unit 104 analyzes a pulse wave for each limb measured by the pulse wave measurement unit 102, thereby obtaining a predetermined pulse wave analysis index (as a pulse wave feature amount of the measurement subject 200 (FIG. 1)). (Hereinafter abbreviated as “analysis index”). In the present embodiment, the “analysis index” represents an index correlated with arteriosclerosis and / or stenosis of blood vessels. That is, the “analysis index” indicates the degree of arteriosclerosis and / or the degree of stenosis of the blood vessel.

Examples of analysis indexes indicating the degree of arteriosclerosis include pulse wave velocity, pulse wave propagation time (PTT: Pulse Transit Time), AI (Augmentation Index), and TR (Traveling time to Reflected wave). . The pulse wave velocity is not limited to the one calculated from the brachial pulse wave and the ankle pulse wave (baPWV), but is calculated from the pulse wave of the other two measurement regions, or one measurement region ( It may be calculated only from the pulse wave at the limb).

Examples of the analysis index indicating the degree of stenosis of the blood vessel include an ankle pulse wave rising feature value and a pulse wave sharpness. The ankle pulse wave rising feature value is calculated, for example, as UT (UT: upstroke time). The UT is calculated as a period during which the ankle pulse wave rises from the rising point to the peak. The sharpness of the pulse wave is calculated as% MAP (normalized pulse wave area). For example,% MAP is calculated as a ratio of the height M from the lowest blood pressure when the pulse wave area is made equal to the peak height H of the pulse wave, that is, the pulse pressure (= M / H × 100).

In the present embodiment, it is described that baPWV is calculated as an analysis index, but other feature quantities as described above may be calculated.

The analysis processing unit 104 performs a process of recognizing the pulse wave shape for each beat (the shape of the pulse wave waveform) from the pulse wave waveforms for a plurality of beats. Specifically, a pulse wave separation process is performed, and the pulse wave waveform is cut out for each beat. Thereby, the pulse wave shape for every beat is recognized. The pulse wave separation process can be realized by a known method such as filter processing or differentiation processing using a specific frequency.

The analysis processing unit 104 accumulates the recognized pulse wave shapes for each beat, and calculates the degree of approximation with the accumulated pulse wave shape (hereinafter also referred to as “accumulated shape”) for each beat. In the present embodiment, “accumulating the pulse wave shape for each beat” means that the pulse wave shape for each beat is averaged, but processing equivalent to averaging may be performed. .

In the present embodiment, “approximation” is a value indicating the degree of approximation of two waveforms, and more specifically, a numerical value representing how much the two waveforms match. . The degree of approximation is obtained by the following equation (1), for example.

FIG. 4 is a diagram for explaining a method of calculating the degree of approximation between the integrated shape and each beat in the embodiment of the present invention.

Referring to FIG. 4, the degree of approximation is calculated as the reciprocal of the area caused by the deviation between the integrated shape Wa and the actually measured i-th pulse wave shape Wi. That is, the degree of approximation can be obtained as the reciprocal of the added value of the difference between the amplitude values Pa and Pi for each sampling time when the rising edge of the pulse is the starting point.

Alternatively, the degree of approximation may be obtained as the reciprocal of the integral value of the difference between the amplitude values Pa and Pi for each sampling time.

Alternatively, the degree of approximation may be obtained by adding a weight to the difference between the amplitude values Pa and Pi and, for example, the reciprocal of the sum of squares of the difference between the amplitude values Pa and Pi as in the following equation (2).

The formula for calculating the degree of approximation is determined based on the results of experiments performed in advance. A setting method (principle) of the calculation formula for the approximation will be described later.

In this embodiment, the degree of approximation between the integrated pulse wave and the whole pulse wave for one beat is determined from the rise of the pulse as a starting point. However, the interval used for calculating the degree of approximation strongly affects the analysis index. You may limit to the range to do. For example, it may be limited to the range from the rising point to the peak of the pulse wave waveform, or may be limited to the front half portion of the pulse wave waveform. In other words, the rear portion that does not affect the calculation of the analysis index in the pulse wave shape for one beat may not be used for the calculation of the degree of approximation.

In the calculation of the degree of approximation, the difference in amplitude value starting from the rise of the pulse is used, but the position of the start point (the position where the two waveforms match) is not limited to the rise of the pulse. For example, a fixed reference position may be set as the starting point, such as starting from the peak of the pulse wave waveform. Alternatively, instead of a fixed reference position, for example, a position where the degree of approximation with the integrated waveform is maximized may be determined for each beat.

In this embodiment, the degree of approximation is calculated. However, the “degree of deviation” from the integrated shape may be calculated. The degree of deviation can be calculated as the reciprocal of the degree of approximation of equations (1) and (2).

The analysis processing unit 104 specifies a pulse having a pulse wave shape determined to have a low degree of approximation with the integrated shape (= high deviation), and excludes the specified beat from the calculation target of the analysis index. Thus, by removing the pulse wave shape having a low degree of approximation with the integrated shape, an unstable pulse wave that is highly likely to be suddenly disturbed by an arrhythmia or body motion is appropriately excluded.

Conventionally, when a pulse waveform for a plurality of beats as shown in FIG. 3 is measured, a doctor determines whether the waveform is disturbed by visual observation. However, according to the present embodiment, the degree of approximation with the integrated shape By calculating, it is possible to discriminate waveform disturbance by calculation.

The analysis processing unit 104 calculates baPWV by analyzing only the pulse waveform of a pulse that is not excluded, that is, a stable pulse waveform. In the present embodiment, two types of baPWV, for example, right upper arm-left ankle pulse wave velocity (hereinafter also referred to as “baPWV_RL”) and upper right arm-right ankle pulse wave velocity, with both left and right ankles as measurement sites. (Hereinafter also referred to as “baPWV_RR”). The reason why the two types of baPWV are calculated in this manner is that these differences can also be used for diagnosis of arterial stenosis in the left lower leg and the right lower leg.

In the present embodiment, the measurement site of the upper arm is set to the right because it is determined as a default, and the left may be used as a reference. For example, when the blood pressure of the upper right arm is lower than the blood pressure of the upper left arm by a predetermined value (for example, 16 to 20 mmHg), the upper left arm may be used as the measurement site instead of the upper right arm. Alternatively, when an instruction to the left of the measurement site is input via the operation unit 6, the left upper arm may be used as the measurement site instead of the upper right arm.

In calculating baPWV_RL and baPWV_RR, only the pulse waveform of a beat not excluded is used for analysis. The analysis processing unit 104 calculates the time difference between the rising positions of the brachial pulse wave and the ankle pulse wave (time Tr and Tl in FIG. 5) for each targeted beat, and calculates the average value of the calculated time as the length of the blood vessel. Each baPWV is calculated by dividing by (= pulse wave propagation distance).

In FIG. 5, the times Tr and Tl indicate the time difference from the rising point P0r of the pulse wave of the upper right arm. When using the left upper arm as the measurement site, the left upper arm—the pulse wave velocity of the left ankle (hereinafter also referred to as “baPWV_LL”) and the left upper arm— The pulse wave velocity of the right ankle (hereinafter also referred to as “baPWV_LR”) is calculated. Times Tr and Tl in FIG. 5 represent pulse wave propagation time (PTT).

Note that the length of the blood vessel necessary for calculating each baPWV is calculated by applying the height of the measurement subject to a predetermined conversion formula. The height of the measurement subject is input by the operation unit 6, for example.

The analysis processing unit 104 further calculates the stability of the pulsation of the whole pulse wave used for calculating the analysis index by accumulating the approximate degree of the pulse wave shape used for calculating the analysis index. Also good. In the present embodiment, for each of baPWV_RL and baPWV_RR, the pulsation stability of the entire pulse wave that is the calculation target is calculated. Since the pulsation stability is derived not from the pulse waveform of all measured beats but from the pulse waveform used for calculating baPWV, it is directly related to the credibility of baPWV. Therefore, it can be said that the stability of each beat calculated by the analysis processing unit 104 indicates the credibility (reliable degree) of the corresponding baPWV.

In addition, when the degree of deviation is calculated instead of the degree of approximation, the value obtained by accumulating the degrees of deviation about the pulse wave shape used for calculating the analysis index is the pulsation of the whole pulse wave used for calculating the analysis index. Calculated as the degree of disturbance.

Each baPWV and each stability calculated by the analysis processing unit 104 are output to the output unit 4. The output unit 4 outputs baPWV_RL and baPWV_RR, and outputs (displays or prints) an index indicating the credibility of the value in association with each baPWV. As an index indicating the credibility of each baPWV, the value calculated as the pulsation stability itself may be output, or the calculated value is replaced with a level value, a mark, or a symbol and output. Also good.

Similarly to the pulse wave measurement unit 102, the blood pressure measurement unit 106 is connected to the adjustment unit 30 and the A / D conversion unit 29, and performs processing for measuring blood pressure in each limb. The blood pressure measurement unit 106 adjusts the internal pressure of the cuff 24 by giving a command signal to the adjustment unit 30 and also detects cuff pressure signals Par (t), Pal (t), Pbr () detected in response to the command signal. t), Pbl (t) is received. The blood pressure measurement unit 106 measures the maximum blood pressure and the minimum blood pressure for each limb of the person 200 to be measured, for example, according to a known oscillometric method. More specifically, for each limb, the cuff pressure is increased at a high speed to a predetermined pressure value, and a predetermined algorithm is applied to a time-series cuff pressure signal detected when the pressure is gradually reduced. Hypertension and diastolic blood pressure are calculated. The blood pressure measurement unit 106 may further measure the pulse rate, average blood pressure, and pulse pressure.

The blood pressure index calculation unit 108 calculates a predetermined blood pressure index based on the blood pressure value measured by the blood pressure measurement unit 106. The “blood pressure index” in the present embodiment represents an index having a correlation with the degree of clogging of blood vessels (degree of arterial stenosis), and specifically includes, for example, ABI (Ankle Brachial Index). In the present embodiment, ABI is calculated using both the left and right ankles and one upper arm as measurement sites. For example, the ratio between the highest blood pressure in the upper right arm and the highest blood pressure in the right ankle and the ratio between the highest blood pressure in the upper right arm and the highest blood pressure in the left ankle are calculated as “ABI_RR” and “ABI_RL”, respectively. In the calculation of each ABI, the measurement site of the upper arm is set to the right when the systolic blood pressure of the upper right arm is higher than that of the left upper arm, and when the systolic blood pressure of the left upper arm is higher than that of the upper right arm. Alternatively, the left upper arm may be used as a measurement site. Further, the average of the highest blood pressures of the upper right arm and the left upper arm may be used as the upper arm blood pressure when calculating the ABI. In the present embodiment, ABI is calculated as a blood pressure index, but other blood pressure feature values may be used.

The measurement result in the blood pressure measurement unit 106 and the ABI_RR and ABI_RL calculated by the blood pressure index calculation unit 108 are output to the output unit 4. The output unit 4 also outputs blood pressure values, ABI_RR and ABI_RL for each limb, together with baPWV_RL, baPWV_RR and an index indicating their credibility. Thereby, a medical worker such as a doctor can more accurately diagnose whether there is a suspicion of arteriosclerosis.

The operations of the pulse wave measurement unit 102, the analysis processing unit 104, the blood pressure measurement unit 106, and the blood pressure index calculation unit 108 described above may be realized by executing software stored in the ROM 12, At least one may be realized by hardware. Further, a part of the processing executed by the analysis processing unit 104 may be realized by hardware.

<About operation>
Next, the operation of pulse wave analysis apparatus 100 in the present embodiment will be described. In the description of the operation, processing executed by the analysis processing unit 104, which is the most characteristic part in the present embodiment, will be described.

FIG. 6 is a flowchart showing the pulse wave analysis processing in the embodiment of the present invention. The process shown in the flowchart of FIG. 6 is stored in advance in the ROM 12 as a program, and the function of the pulse wave analysis process is realized by the CPU 10 reading and executing this program.

It is assumed that the pulse wave waveform for each limb measured by the pulse wave measuring unit 102 is stored in the RAM 14 or the storage device 8 when the pulse wave analysis process is started. That is, the pulse wave analysis process in the present embodiment is not limited to the one performed immediately after the pulse wave measurement, and may be performed on a pulse wave waveform measured in the past stored in the storage device 8. Good.

Referring to FIG. 6, the analysis processing unit 104 performs a process of dividing a stored pulse wave waveform for a plurality of beats for each limb that is a measurement site (step S <b> 102). Thereby, the pulse wave waveform for a plurality of beats is cut out in units of one beat, and the pulse wave shape for each beat is recognized.

Subsequently, the analysis processing unit 104 averages the pulse wave shapes of all recognized beats for each limb (step S104), and approximates the averaged pulse wave shape (integrated shape) to each pulse wave shape. The degree is calculated (step S106). For example, the above equation (1) is used to calculate the degree of approximation. The degree of approximation of each pulse wave calculated for each limb is temporarily recorded in the RAM 14.

The analysis processing unit 104 performs a beat exclusion process with a low degree of approximation (step S108). Specifically, first, for each limb, a pulse wave shape whose degree of approximation does not satisfy a certain standard (that is, the degree of approximation is equal to or less than a predetermined threshold value) is specified, and the specified pulse wave shape is designated as baPWV. Exclude from calculation. Note that the threshold used for specifying the pulse wave waveform is not limited to a predetermined value. For example, a threshold value may be determined from the average degree of approximation of all beats, and a pulse wave shape that does not satisfy the criterion (determined threshold value) may be specified as an exclusion target. As a result of the exclusion process, information on whether or not it is used for calculating baPWV is temporarily recorded in the RAM 14.

FIG. 7 is a diagram illustrating an example of the exclusion process result in step S108 of FIG.
Referring to FIG. 7, the pulse wave shapes of the upper right arm, left upper arm, right ankle and left ankle are excluded from the calculation target in association with each beat i (i = 1, 2, 3,..., N). Information on whether or not has been recorded is recorded. In the present embodiment, for example, “1” is recorded in the column corresponding to the beat number determined as the pulse wave waveform to be excluded, and “0” is set otherwise. In addition, the holding method of the exclusion process result in each limb is not limited to the example as shown in FIG.

When the exclusion process is finished, baPWV (pulse wave propagation velocity) is calculated reflecting the process result (step S110). In the present embodiment, both baPWV_RL and baPWV_RR are calculated by excluding beats determined to have a low degree of approximation as a result of the exclusion process in step S108.

Here, the calculation method of each baPWV will be described assuming that the result as shown in FIG. 7 is recorded. When calculating baPWV_RL, the pulse wave of the upper right arm and the pulse wave of the left ankle are used. Referring to FIG. 7, the pulse wave of the third beat of the upper right arm and the pulse wave of the sixth beat of the left ankle are recorded as exclusion targets. Therefore, baPWV_RL is calculated by excluding the third and sixth beats. More specifically, for each beat other than the third beat and the sixth beat, the pulse wave propagation time of the pulse wave of the upper right arm and the left ankle is calculated, and the calculated average value of the pulse wave propagation time and the length of the blood vessel are calculated. Based on the estimated value, baPWV_RL is calculated.

When calculating baPWV_RR, the pulse wave of the upper right arm and the pulse wave of the right ankle are used. Referring to FIG. 7, the pulse wave of the third beat of the upper right arm and the pulse waves of the fifth and sixth beats of the right ankle are recorded as exclusion targets. Therefore, baPWV_RR is calculated by excluding the third, fifth and sixth beats. More specifically, for each beat other than the third beat, the fifth beat, and the sixth beat, the pulse wave propagation time of the pulse wave of the upper right arm and the right ankle is calculated, and the average value of the calculated pulse wave propagation times And baPWV_RR is calculated from the estimated value of the length of the blood vessel.

As described above, according to the present embodiment, the greatly disturbed pulse wave waveform is not used for calculating each baPWV, so that the analysis index can be calculated with high accuracy. Further, by accumulating measured waveforms, a pulse wave shape that is a reference for calculating the degree of approximation is obtained. Therefore, it is possible to specify a pulse wave shape that should be appropriately excluded according to the pathological condition or medical condition of the measurement subject at the time of measurement, or measurement conditions (such as immediately after medication).

Next, the analysis processing unit 104 calculates the authenticity of the baPWV (step S112). In the present embodiment, the pulsation stability of the entire pulse wave used for calculating baPWV_RL and baPWV_RR is calculated. Specifically, the stability of the pulsation of the whole pulse wave used for calculating baPWV_RL, that is, the credibility of baPWV_RL is calculated by accumulating (for example, averaging) the approximation of the beat used for calculating baPWV_RL. Is done. In the calculation of baPWV_RL, the pulse waves of the 3rd and 6th beats were excluded using FIG. 7 as an example. Therefore, the credibility of baPWV_RL is for the beats of the right upper arm and left ankle other than the 3rd and 6th beats. It is expressed as a value obtained by averaging the degree of approximation.

More specifically, among the pulse wave shape of the upper right arm, the average value of the approximations of the beats other than the third and sixth beats and the pulse wave shape of the left ankle other than the third and sixth beats The average value of the degree of approximation of beats is obtained. A value obtained by further averaging these average values is calculated as the stability of the entire pulse wave used for the calculation.

Alternatively, the approximation degrees of the beats other than the third and sixth beats in the pulse wave shape of the upper right arm and the beats other than the third and sixth beats in the pulse wave shape of the left ankle are averaged. The calculated value may be calculated as the stability of the entire pulse wave used for the calculation.

The authenticity of baPWV_RR is calculated in the same way. In the calculation of baPWV_RR, the pulse waves of the third beat, the fifth beat, and the sixth beat are excluded in FIG. 7 as an example. Therefore, the credibility of baPWV_RR is different from the third beat, the fifth beat, and the sixth beat. It is calculated by accumulating (for example, averaging) the degree of approximation of the beat with the accumulated shape.

As described above, the authenticity of each baPWV is obtained by accumulating the degree of approximation of all the beats used for calculating the index after individually evaluating the degree of approximation with the accumulated shape. Therefore, the influence of one beat on the whole is equivalent to the conventional method for calculating baPWV (calculating the pulse wave propagation time for each beat and dividing the estimated blood vessel length by the average thereof) Can be.

When the above analysis processing is completed, each analysis result is output to the output unit 4 (step S114). In the present embodiment, the output unit 4 functioning as a printer (driver) prints the obtained analysis result on a paper medium. For example, analysis result information as shown in FIG. 8 is printed on the paper medium.

FIG. 8 is a diagram showing an output example of analysis result information in the embodiment of the present invention.
Referring to FIG. 8, on the paper medium, baPWV_RR value 91, baPWV_RR credibility index 92, baPWV_RL value 93, and baPWV_RL credibility index 94 are printed as a result of pulse wave analysis. Yes. The index indicating the credibility is indicated by, for example, symbols in five stages of “++++”, “++”, “+”, “±”, and “−” in descending order of credibility (high stability). It is assumed that these symbols to be displayed are stored in advance in the ROM 12 in association with the numerical value range of stability.

As described above, by placing the

indexes

92 and 94 indicating the credibility of these values immediately below the respective baPWV values 91 and 93, these indexes are printed in association with each other. As a result, a medical worker such as a doctor can perform a more correct diagnosis by considering not only the value of baPWV output as an analysis index but also the high credibility of the index.

As described above, the pulse wave analysis apparatus 100 of the present embodiment also measures the blood pressure of each limb and calculates ABI_RR and ABI_RL. Therefore, in FIG. 8, the blood pressure 81 of the upper right arm, the blood pressure 82 of the right ankle, the blood pressure 83 of the left upper arm, the blood pressure 84 of the left ankle, the ABI_RR value 85, and the ABI_RL value 86 are further output.

The units of baPWV and blood pressure value shown in FIG. 8 are “cm / s” and “mmHg”, respectively.

Further, the above-mentioned UT and% MAP may be output as the analysis result information. Further, a graph as shown in FIG. 9 may be output.

FIG. 9 is a diagram showing another output example of the analysis result information in the embodiment of the present invention.
FIG. 9 is a graph with baPWV on the vertical axis and ABI on the horizontal axis. In this graph, the arteriosclerosis level determined by baPWV and ABI is shown in advance so as to be distinguishable (for example, color-coded). In this graph, the arteriosclerosis levels of the right lower leg and the left lower leg are indicated by predetermined marks, characters, symbols, and the like.

In FIG. 9, the level of arteriosclerosis of the right lower leg is represented by a black triangle plotted at the intersection of baPWV_RR calculated by the analysis processing unit 104 and ABI_RR calculated by the blood pressure index calculation unit 108. It is indicated by the position of the mark. The arteriosclerosis level of the left lower leg is indicated by the position of a white triangle mark plotted at the intersection of baPWV_RL calculated by the analysis processing unit 104 and ABI_RL calculated by the blood pressure index calculation unit 108. Yes.

In the present embodiment, both the measured baPWV_RR and baPWV_RL are output as the analysis result information. However, of the measured baPWV_RR and baPWV_RL, only the baPWV having the higher credibility (stability) calculated in step S112 in FIG. 6 may be output as the pulse wave analysis result. For example, since a report for presentation to a patient generally prints only simple information, only one baPWV may be output only in a report for a patient. In such a case, a graph as shown in FIG. 10 may be printed instead of the graph as shown in FIG. In FIG. 10, only the baPWV with higher stability is plotted in the graph in which the vertical axis represents baPWV and the horizontal axis represents ABI. In this way, by outputting only baPWV with higher credibility (stability), it is possible to perform more appropriate judgment than when the higher value baPWV or the average value of the left and right baPWV is plotted. Diagnosis can be possible.

<Approximation formula>
As described above, in this embodiment, the degree of approximation with the integrated pulse wave for each beat is used to calculate the analysis index with high accuracy. Therefore, the calculation formula for the degree of approximation needs to be appropriately determined by experiment.

FIG. 11A to FIG. 27B are diagrams showing examples in which the pulse wave shapes for each beat are overlapped starting from the rising position for each of the measurement IDs 1 to 17. In each figure, FIGS. 11A to 27A show pulse wave waveforms measured for a plurality of beats along the time axis, and FIGS. 11B to 27B show the waveforms shown in FIGS. 11A to 27A. A state in which the pulse wave shapes for the beats are overlapped starting from the rising position is shown. The value on the vertical axis in FIGS. 11A to 27A represents the output value obtained by digitally converting the pressure, and the value on the vertical axis in FIGS. 11B to 27B represents the amplitude. Further, the horizontal axis delimiters in FIGS. 11B to 27B represent sampling points.

FIG. 28 is a diagram showing the relationship between the ranking of the degree of approximation calculated by the apparatus and the ranking of the degree of approximation by the reader when the pulse wave waveforms of FIGS. 11A to 27B are targeted.

“Index” in FIG. 28 is an average value of the approximation degree (with an integrated shape not shown) calculated for each measurement ID by the above calculation formula (1) by a predetermined conversion formula. It is shown by. "Equipment rank" indicates the rank in ascending order of the index indicated by 100 minutes. The “reader ranking” is determined for each beat (not shown in the figure) manually determined for each measurement ID by a person having sufficient knowledge about pulse waves, such as a medical worker or a developer of the pulse wave analysis device 100. Shows the average degree of approximation (with shape).

FIG. 29 is a diagram showing the correlation between the approximate ranking by the apparatus and the approximate ranking by the reader shown in FIG. As shown in FIG. 29, in the two-dimensional coordinate plane, the determination coefficient R2 of the correlation between the two when the “human judgment order (reader order)” is taken on the Y axis and the “device judgment order” is taken on the X axis. Is represented by 0.6844.

As described above, when the degree of approximation is calculated by the above formula (1), a result close to the reader's rank can be obtained. However, the degree of reader's rank matches the judgment order of the device. It is desirable that an equation for determining, that is, an equation such that the determination coefficient R2 approaches 1.0 is determined by experiment. This is because, conventionally, the disturbance of the waveform (arrhythmia or body movement) has been determined by visual observation by a human such as a medical attendant.

<Modification 1>
In the above embodiment, when baPWV is calculated, the measurement site of the upper arm is set to the measurement site of the arm (for example, the right) determined as the default. Alternatively, it is determined whether the upper arm used for calculating baPWV is right or left based on the blood pressure difference between the upper right arm and the left upper arm.

However, based on the degree of approximation calculated by the analysis processing unit 104, the measurement part of the upper arm used for calculating baPWV may be determined.

Specifically, the following processing may be performed in step S110 (calculation of pulse wave velocity) in FIG. Also in the following description, it is assumed that the calculation of baPWV using the pulse wave of the upper right arm is determined as a default.

In the immediately preceding step S108 (exclusion process), the analysis processing unit 104 determines in advance the average value “AVr” of the degree of approximation for the beat “BTr” that is not excluded from the calculation target in the pulse wave of the upper right arm. It is determined whether or not the threshold value is exceeded. When it is determined that the average value AVr is less than the threshold value, the pulse wave of the left upper arm is used for calculating baPWV. Alternatively, if the average value “AVl” of the degree of approximation of the beat “BTl” that is not excluded from the calculation target of the pulse wave of the left upper arm is also less than a predetermined threshold value, the user is notified to perform measurement again. It is good as well.

Alternatively, the average value AVr and the average value AVl may be compared, and the pulse wave of the part with the higher value may be used for calculating baPWV.

In the example of FIG. 7, the above beat BTr represents a beat other than the third beat that has a low degree of approximation with the integrated pulse wave of the upper right arm. Alternatively, the beat BTr may represent a beat other than the third, fifth, and sixth beats in consideration of the exclusion result of the ankle pulse wave. Similarly, the above-mentioned beat BT1 represents a beat other than the fourth beat that has a low degree of approximation with the integrated pulse wave of the left upper arm. Alternatively, the beat BT1 may represent a beat other than the 4th to 6th beats in consideration of the exclusion result of the ankle pulse wave.

Similarly to the brachial pulse wave, only the left or right pulse wave is used for calculating the baPWV, and only one baPWV is calculated based on the brachial pulse wave and the ankle pulse wave where the pulse wave is stable. It is good as well.

<Modification 2>
In the above embodiment, baPWV_RL and baPWV_RR are measured, but PWV that can be calculated from a pulse wave at one measurement site may be used.

When calculating the PWV from the pulse wave at one measurement site, the PWV is obtained by dividing the pulse wave propagation distance (Lpt) by the pulse wave propagation time (PTT). The propagation distance is the so-called trunk length, which is twice the distance between the heart and the bifurcation of the iliac artery, which is the reflection site. The trunk length is proportional to the height. Although the pulse wave propagation distance cannot be directly measured, it can be obtained using a predetermined conversion formula. PTT is calculated by applying Tpp and TR shown in FIG. 30 to a predetermined conversion formula. Tpp represents the time interval between the appearance time of the peak (maximum point) of the ejection wave, which is a traveling wave, and the appearance time of the peak (maximum point) of the reflected wave. TR represents the time interval between the appearance time of the ejection wave and the appearance time of the reflected wave where the traveling wave is reflected back from the bifurcation of the iliac artery. These can also be used as an index for determining the degree of arteriosclerosis. In FIG. 30, Tpp is represented by the time interval between the point A which is the ejection wave peak point and the point B which is the reflected wave peak point. In FIG. 30, TR is represented by a time interval from the rising point of the ejection wave to the rising point of the reflected wave.

Alternatively, AI may be calculated as an analysis index. In that case, referring to FIG. 30, the analysis processing unit (104) extracts the amplitude P2 at the point B with respect to the amplitude P1 at the point A, and the AI value is obtained by dividing the amplitude P1 by the amplitude P2. .

When calculating such PWV or AI as an analysis index, the degree of approximation may be calculated by limiting the range that affects the index calculation to a range that includes from the rising point of the pulse to the reflected wave peak.

<Modification 3>
Although the pulse wave analysis device 100 in the above embodiment has been described as including the detection unit 20, the cuff 24, and the information processing unit 1, the pulse wave analysis device is a general-purpose computer that does not include the detection unit 20 and the cuff 24. It may be realized. That is, in the present embodiment, the pulse wave analysis device realizes the pulse wave analysis processing as shown in FIG. 6 if the function of the analysis processing unit 104 that is typically realized by the CPU 10 is included. Can do. The general-purpose computer may have the same hardware as the information processing unit 1.

The pulse wave analysis method performed by the pulse wave analysis apparatus according to the present embodiment and each modification may be provided as a program. Such a program is recorded on a non-transitory recording medium in which the program can be read by a computer. Such “computer-readable recording medium” includes, for example, an optical medium such as a CD-ROM (Compact Disc-ROM), a magnetic recording medium such as a memory card, and the like. Further, such a program can be recorded on a computer-readable recording medium and provided as a program product. A program can also be provided by downloading via a network.

The program according to the present embodiment is a program module that is provided as a part of a computer operating system (OS) and calls necessary modules in a predetermined arrangement at a predetermined timing to execute processing. There may be. In that case, the program itself does not include the module, and the process is executed in cooperation with the OS. A program that does not include such a module can also be included in the program according to the present embodiment.

Further, the program according to the present embodiment may be provided by being incorporated in a part of another program. Even in this case, the program itself does not include the module included in the other program, and the process is executed in cooperation with the other program. Such a program incorporated in another program can also be included in the program according to the present embodiment.

The provided program product is installed in a program storage unit such as a hard disk and executed. Note that the program product includes the program itself and a storage medium in which the program is stored.

The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

According to the present invention, the pulse wave analysis apparatus can calculate the pulse wave analysis index using only stable beats with little influence of body motion or the like.

1 information processing unit, 2 control unit, 4 output unit, 6 operation unit, 8 storage device, 20ar, 20al, 20br, 20bl detection unit, 22al, 22ar, 22bl, 22br piping, 24ar, 24al, 24br, 24bl cuff, 25al , 25ar, 25bl, 25br pressure pump, 26al, 26ar, 26bl, 26br pressure regulating valve, 27al, 27ar, 27bl, 27br piping, 28al, 28ar, 28bl, 28br pressure sensor, 29al, 29ar, 29bl, 29br A / D converter , 30 adjustment unit, 100 pulse wave analysis device, 102 pulse wave measurement unit, 104 analysis processing unit, 106 blood pressure measurement unit, 108 blood pressure index calculation unit, 200 person to be measured.

Claims

A storage unit (8) for storing pulse waveforms for a plurality of beats;
An analysis processing unit (2) for performing a process for calculating a pulse wave analysis index by analyzing the pulse waveform of the plurality of beats,
The analysis processing unit (2)
The pulse wave shape for each beat constituting the pulse wave waveform for the plurality of beats is accumulated,
Calculating the pulse wave analysis index by excluding beats having a low degree of approximation between the accumulated pulse wave shape and the pulse wave shape for each beat from the calculation target;
A pulse wave analysis device (1) further comprising an output unit (4) for outputting the calculated pulse wave analysis index as an analysis result.
The analysis processing unit (2) further calculates the stability of pulsation by accumulating the degree of approximation of the pulse wave shape used for calculating the pulse wave analysis index,
The pulse wave analysis device (1) according to claim 1, wherein the output unit (4) further outputs the stability as an index indicating the credibility of the pulse wave analysis index.
The storage unit (8) stores the pulse waveform for the plurality of beats for each limb,
The analysis processing unit (2) accumulates the pulse wave shape for each beat for each limb, and calculates the approximation, the pulse wave analysis index, and the stability,
The pulse wave analysis device (1) according to claim 2, wherein the output unit (4) outputs the pulse wave analysis index having the higher stability as the analysis result.
The storage unit (8) stores a pulse waveform for a plurality of beats for the left and right limbs,
The analysis processing unit (2) calculates the degree of approximation for each limb, and calculates the pulse wave analysis index using a pulse wave shape of the limb having the higher degree of approximation. The pulse wave analysis device (1) according to the first term of the range.
The said analysis process part (2) is limited to the range which influences calculation of the said pulse wave analysis parameter | index among the pulse wave shapes for every said beat, The said approximation degree is calculated to Claim 1 characterized by the above-mentioned. The described pulse wave analyzer (1).
The pulse wave analysis device (1) according to claim 1, wherein the pulse wave analysis index indicates a degree of arteriosclerosis and / or a degree of stenosis of a blood vessel.
The pulse wave analysis device (1) according to claim 6, wherein the pulse wave analysis index includes a pulse wave velocity as an index indicating the degree of arteriosclerosis.
A pulse wave detector (20ar, 20al, 20br, 20bl) for detecting a pulse wave of the limb,
The said pulse wave analysis part (2) measures the pulse wave waveform for the said several beats based on the detection signal from the said pulse wave detection part (20ar, 20al, 20br, 20bl). 2. The pulse wave analyzer (1) described in 1.
A recording medium recording a pulse wave analysis program for causing a computer to function as a device for analyzing a pulse wave,
The pulse wave analysis program is stored in the computer.
A step of accumulating a pulse wave shape for each beat constituting a pulse wave waveform for a plurality of beats stored in the storage unit;
Calculating a pulse wave analysis index by excluding beats having a low degree of approximation between the accumulated pulse wave shape and the pulse wave shape for each beat from the calculation target;
A recording medium that causes a computer to execute the step of outputting the calculated pulse wave analysis index as an analysis result.